The present invention relates generally to communication handovers between base stations of a radio communication system, such as a BLUEPAC (Bluetooth public access) system. More particularly, the present invention relates to a manner by which to facilitate communication handovers of a Bluetooth, or other, mobile device to a target base station. In one implementation, information related to the target base station is provided to the mobile device by the base station with which the mobile device is first associated. In another implementation, separate, dedicated transmitters are provided. A first set of dedicated transmitters is utilized to perform setup operations with the mobile device, and a second set of transmitters is utilized to perform regular data transmissions.
New types of communication systems have been made possible as a result of advancements in communication technologies. Such new types of communication systems have generally permitted increased rates of data transmission or made more convenient, or even made possible, the transmission of data.
The advancements in communication technologies have, for example, permitted the introduction, and popularization, of new types of radio communication systems. Radio communication systems are advantageously utilized as communication paths formed during operation thereof include radio links. By utilization of radio links to form at least portions of the communication paths upon which information is communicated, the use of such portions of the communication paths do not require conventional wirelines. Increased communication mobility, relative to conventional wireline communication systems, is thereby generally possible in a radio communication system.
The technology, referred to as Bluetooth, is exemplary of advancements in communication technologies which has permitted new communication possibilities. A BLUEPAC (Bluetooth public access) system is a communication system which utilizes Bluetooth technology. Low power, high-frequency (2.4 GHz) signals are generated to communicate information between a mobile Bluetooth device and a Bluetooth base station. The communication range of a Bluetooth device is relatively small, e.g., in the range of 10 meters. When the Bluetooth device forms a mobile device, network infrastructure, of which a Bluetooth base station forms a portion, must be able to provide for communications with the mobile device to permit the advantages provided by the mobility of the mobile device. Typically, a plurality of base stations are utilized, networked together into a LAN (local area network). Analogous to handover procedures performed in conventional cellular communication systems, handover procedures are defined in a BLUEPAC system as the mobile device moves throughout an area encompassed by the system.
That is to say, when the mobile device leaves a coverage area, i.e., cell, defined by a first base station and enters a coverage area defined by a second base station, handover operations are performed to handover communications from the first base station to the second base station, thereby to permit continued communication activities to be maintained.
Existing procedures by which to perform handovers of communications are less than ideal. Namely, in existing BLUEPAC systems, an inappropriately long period of time might be required for such communications to be xe2x80x9chanded-overxe2x80x9d from a first base station to a target base station.
In conventional procedures, Bluetooth (BT) baseband protocols are utilized. Using such protocol, the mobile device is required to perform inquiry and page procedures in which inquiry and page scans are performed. During such periods, the affected base stations are not able to perform regular data transmissions to other mobile devices. Also, the timing perimeter of a target base station does not necessarily correspond to the timing perimeter of the base station, and that of the mobile device which is synchronized thereto, from which communications are to be handed-over. Such time differences also might cause a delay in the effectuation of handover of communications to the target base station.
If a manner could be provided by which better to effectuate handover of communications to a target base station in a BLUEPAC, or other radio, communication system, improved communication performance would result.
It is in light of this background information related to radio communication systems that the significant improvements of the present invention have evolved.
The present invention, accordingly, advantageously provides apparatus, and associated method, by which to facilitate efficient handover of communications of a mobile Bluetooth, or other, device to a target base station. Through operation of an embodiment of the present invention, handover of communications to the target base station are effectuated more quickly than generally permitted utilizing convention techniques, thereby, to improve handover procedures.
An embodiment of the present invention is advantageously implemented in a BLUEPAC (Bluetooth public access) communication system. A BLUEPAC system includes, for instance, a LAN (local area network) including Bluetooth base stations capable of communicating Bluetooth-compatible signals. Each of the base stations define a coverage area within which communications with a mobile Bluetooth device is possible. When the mobile Bluetooth device exits the coverage area associated with one of the base stations and enters the coverage area associated with another of the base stations, communication handover operations are performed. Conventional Bluetooth baseband protocols are utilized to effectuate a hand-off. However, the mobile Bluetooth device does not know the address of the target base station. To determine the address of the target base station, therefore, the mobile device performs an inquiry procedure utilizing a special dedicated inquiry access code reserved for base stations. The inquiry procedure might require a relatively long time period, e.g., several seconds, to be performed. And, once the address of the target base station is obtained by the mobile device, a page procedure must be performed to create a connection with the target base station. Timing disparities between the mobile device and the target base station might further delay, e.g., by several seconds, the creation of the connection.
In one aspect of the present invention, additional information is provided to the mobile Bluetooth device regarding one or more potential target base stations. The information provided to the mobile Bluetooth device facilitates effectuation of communications to a target base station. In one implementation, address information associated with the one or more target base stations is provided to the Bluetooth device. The address information provided to the Bluetooth device by the base station with which the mobile device is associated obviates the conventional requirement that the mobile device perform an inquiry procedure to determine the address of the target base station. In another implementation, timing information associated with one or more target base stations is provided to the mobile device by the base station with which the mobile device is associated. Time delay in creation of a connection with the target base station due to an erroneous estimation of the target base station""s timing is reduced.
In another aspect of the present invention, additional transmitters are provided to the Bluetooth base station to facilitate improved rates of connection of a Bluetooth mobile device with the base station. Separate, dedicated, transmitters are provided in which a first set of transmitters which are dedicated to perform connection setup operations. And, at least one additional set of dedicated transmitters is utilized to perform regular data transmissions. Bandwidth available to the transmitters is thereby utilized more efficiently as contrasted to conventional operation of Bluetooth devices required to perform regular page and inquiry scans. Fewer delays associated with performing connection setup procedures and data transmissions result, thereby improving the efficiency of operation of communications in the BLUEPAC communication system.
In a further aspect of the present invention, both the additional information is broadcast to the mobile Bluetooth devices to be used by the Bluetooth devices to facilitate effectuation of communication handover. And, also, separate, dedicated transmitters are provided to the base station, separately to perform the separate connection setup and regular data transmission functions. Amounts of time required to effectuate communication handovers are thereby reduced both because of the transmission of the additional information to the mobile device and due to the use of the separate, dedicated transmitters.
In one implementation, the base station includes apparatus which collects information related to timing perimeters and addresses of neighbor base stations which form target base stations and communication handover operations. Additional apparatus is provided to the base station to convert the collected information into a signal which is broadcast to mobile Bluetooth devices positioned within the coverage area associated with the base station.
In another implementation, apparatus is provided to a mobile Bluetooth device to detect signals generated by a base station with which the mobile device is associated. The signals include information related to one or more potential target base stations to which communications can be handed over in communication handover procedures. The apparatus further includes a storage element at which the informational content of the signal is stored, to be retrieved during handover procedures.
By reducing the amount of time required to effectuate handover of communications, a manner is provided through operation of an embodiment of the present invention to facilitate efficient communication handovers.
In these and other aspects, therefore, apparatus, and an associated method, is provided for facilitating handover of communications in a radio communication system. The radio communication system includes network infrastructure having a first base station and at least a second base station. The first base station defines a first coverage area, and the second base station defines a second coverage area. Each of the first and at least second base stations is selectably operable to communicate with a mobile terminal when the mobile terminal is positioned in a corresponding one of the first coverage area and the second coverage area. Handover of communication occurs when the mobile terminal moves between the first and second coverage areas. An information collector is associated with the first base station. The information collector collects information associated with the second base station during operation of the radio communication system. A collected-information signal generator is coupled to receive the information collected by the information collector. The collected-information signal generator generates and broadcasts a collected-information signal to the mobile terminal to be detectable by the mobile terminal when the mobile terminal is positioned within the first coverage area. The information contained in the collected-information signal is used by the mobile terminal to effectuate handover of communications between the first base station and the second base station.
Also in these and other aspects, apparatus, and an associated method, is provided for a first base station operable in a radio communication system having network infrastructure of which the first base station forms a portion. The first base station defines a first coverage area and is operable to communicate with a mobile terminal when the mobile terminal is positioned in the first coverage area. A first Bluetooth transmitter forms a setup connector capable of performing connection setup operations with the mobile terminal. At least one Bluetooth transmitter is provided to which the mobile terminal is directed subsequent to connection setup operations. The at least one additional Bluetooth transmitter performs regular data transmissions with the mobile terminal.